Green Fabrication of Porous Ceramics Using an Aqueous Electrophoretic Deposition Process

We prepared porous ceramic depositions using gas generation in an aqueous electrophoretic deposition (EPD) process. Especially, this aqueous EPD process in combination with a sintering step could advantageously result in unique porous deposition containing many unidirectionally aligned continuous pores. The aqueous EPD process has environmental and cost reduction advantages.     

The Scan Time Effect on the Particle Size Distribution Measurement in the Scanning Mobility Particle Sizer System

The scan time effect in the scanning mobility particle sizer was confirmed. The magnitude of this effect was shown in a typical situation. The cause of this scan time effect is the mixing process described by Russell et al. (1995). In that case, the result obtained at the longer scan time is the more accurate one.     

Analysis and inhibition of progressive photomask contamination in long‐term use for liquid‐crystal panel production

Abstract— Progressive contamination on photomasks has become a serious concern as a source of defects in long‐term TFT‐LCD manufacturing. The chemical structure and mechanism of formation of such contamination was determined, an accelerated test to replicate it was devised, and a means of inhibiting it was developed.     

Ethanol demand in Brazil: Regional approach

Successive studies attempting to clarify national aspects of ethanol demand have assisted policy makers and producers in defining strategies, but little information is available on the dynamic of regional ethanol markets. This study aims to analyze the characteristics of ethanol demand at the regional level taking into account the peculiarities of the developed center-south and the developing north-northeast regions. Regional ethanol demand is evaluated based on a set of market variables that include ethanol price, consumer’s income, vehicle stock and prices of substitute fuels; i.e., gasoline and natural gas. A panel cointegration analysis with monthly observations from January 2003 to April 2010 is employed to estimate the long-run demand elasticity. The results reveal that the demand for ethanol in Brazil differs between regions. While in the center-south region the price elasticity for both ethanol and alternative fuels is high, consumption in the north-northeast is more sensitive to changes in the stock of the ethanol-powered fleet and income. These, among other evidences, suggest that the pattern of ethanol demand in the center-south region most closely resembles that in developed nations, while the pattern of demand in the north-northeast most closely resembles that in developing nations.     

Detection and Extraction of Waveform Shapes for Local Signals Using Characteristic Waveform Template

Since local signals appear time‐locally and their waveforms are steep, conventional signal processing methods are generally inadequate to detect them. In this paper, by focusing on amplitude distribution forms of an observed signal, a simple signal processing method is proposed to detect the local signals and extract their waveform shapes simultaneously. Concretely, a characteristic waveform template which consists of representative data series of a simplified target local signal is newly introduced, and a certain event regulated with it is adopted. The local signals can be detected by evaluating whether the amplitude distribution forms of observed signals are associated with the event, and substitution of conditional events for associated events improves detection performance. In addition, the proposed method has been extended to extract waveform shapes by introducing an enhanced waveform template, and automatic detection and extraction of waveform shapes can be performed simultaneously. The proposed method is applied to simulation signal data, and its effectiveness is confirmed by detection performance and extracted waveform shapes for the local signals. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(3): 37–47, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21074     

Sensorless suppression control for frame vibration of PMSM

It is well known that frame vibration occurs in driving permanent magnet synchronous motors (PMSM). The authors have suggested a method for suppression of frame vibration by means of Fourier series and repetitive control. The method requires an acceleration sensor and a position sensor. However, the use of such a sensor is not desirable from the point of view of system cost. Therefore, this paper proposes a method of sensorless suppression control of frame vibration. The effectiveness of the proposed method is illustrated by experiments. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(3): 53–61, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21048     

Characterization and gas permeation properties of UV‐cured fluorine‐containing telechelic polyimide membranes with a crosslinker

The characterization and gas permeation properties of ultraviolet (UV)‐cured fluorine‐containing telechelic polyimide membranes and end‐capped with a crosslinker with acryloyl groups were investigated. Membrane formation property was improved by the addition of crosslinker by using UV irradiation. The densities of UV‐cured membranes were almost similar to each other, and high gel fraction was shown on the UV‐cured membranes. This result suggests that the crosslinker promotes crosslink reaction at the polymer chain ends and does not induce appreciable membrane densification. Furthermore, the gas permeability of the UV‐cured membranes was higher than that of the membrane without the crosslinker. The higher gas permeability is due to the new crosslink structure formed at the polymer chain ends, which was promoted by the crosslinker after UV irradiation, but did not induce appreciable membrane densification. The use of a BEI crosslinker in the telechelic polyimide membranes promoted the crosslink reaction and increased the H₂ selectivity because H₂ permeability was not sensibly affected by the crosslink reaction. POLYM. ENG. SCI., 54:1089–1099, 2014. © 2013 Society of Plastics Engineers     

Generation of Nanoparticles of Lubricating Motor Oil for Inhalation Studies

Recent studies suggest that most 20–30 nm nanoparticles measured at roadsides are composed mainly of organic carbon derived from lubricating motor oil. Therefore, a simple particle generation system has been developed for controlled production of 20–30 nm nanoparticles of lubricating motor oil for inhalation toxicology studies by means of vapor condensation without addition of nuclei. Quasi-monodisperse particles with a modal diameter located at 20 nm and total number concentrations above 10 ⁶ cm ^?3 were generated. Ten 2-h particle generation reproducibility tests were conducted, in which stability and repeatability of particle size and total number concentration were good. Organic carbon is a major component of oil particles, and organic analysis showed that the compositions of oil particles were not subjected to distillation of organic compounds through evaporation to condensation. Using the nose-exposure system connected to the particle generation system, toxicity of 20-nm particle organic compounds of lubricating motor oil can be assessed by inhalation studies of experimental animals.     

Characterization of Films with Thickness Less than 10 nm by Sensitivity-Enhanced Atomic Force Acoustic Microscopy

We present a method for characterizing ultrathin films using sensitivity-enhanced atomic force acoustic microscopy, where a concentrated-mass cantilever having a flat tip was used as a sensitive oscillator. Evaluation was aimed at 6-nm-thick and 10-nm-thick diamond-like carbon (DLC) films deposited, using different methods, on a hard disk for the effective Young's modulus defined as E/(1 - ν ²), where E is the Young's modulus, and ν is the Poisson's ratio. The resonant frequency of the cantilever was affected not only by the film's elasticity but also by the substrate even at an indentation depth of about 0.6 nm. The substrate effect was removed by employing a theoretical formula on the indentation of a layered half-space, together with a hard disk without DLC coating. The moduli of the 6-nm-thick and 10-nm-thick DLC films were 392 and 345 GPa, respectively. The error analysis showed the standard deviation less than 5% in the moduli.